docs: def _remove_tag_helper(self, p_key, p_value):
          """
          Removes a tag from the internal todo dictionary. Only those instances
          with the given value are removed. If the value is empty, all tags with
          the given key are removed.
          """
          tags = self.fields['tags']
  
          try:
              tags[p_key] = [t for t in tags[p_key] if p_value != "" and t != p_value]
              if len(tags[p_key]) == 0:
                  del tags[p_key]
          except KeyError:
              pass